Propeller drive



Julie 9, 1942. J. LgDwlNKA 'PRQPELLER DRIVE Filed Nov. 29. 19.58

`INVENTOR:

and eciency, as well as simplicity and rugged 30 cover plate 28 having an oil washer 36. The

Patented-June9, 19,42' l l f i l U'Nirsp ,STATES mrri'zlwr orifice rnoPELLEn DRIVE Joseph Ledwinka, Philadelphia, Pa., assignor to Budd Manufacturing Company, Philadelphia, Pa., a corporation of Pennsylvania Application November 29, 1938, Serial No. 242,935

"s clama. (ci. 'J4-389) tions v In single engine,air-craft and dirigible aircraft the torsion resulting from the reaction of ing is employed for purposes of illustration very great undesirable effects. In planes where several views;

two propellers are employed by reversely rotating Figure luis a longitudinal section illustrating one propeller, its torque .becomes neutralized by the general arrangement of drivev 'mechanism the other propeller. However, in any case where l and supporting structure and single propellers are employed; such` propeller Figure 2 is an elevation view of the main cenreaction must be transmitted through frame and tral support member. wing members of the plane, thus setting up addi- Referring more particularly t0 Figure 1, it Will tional stresses which must be reckoned with in be `Se`en that there iS ShOWn therein an engine air craft design. housing i@ having secured thereto a gear housing By employing dual propellers arranged to roi2 in which are journalled propeller drive sleeves tate about the same axis and closely adjacent one It and f6, each carrying a propeller hub i8 another, the reaction torque of one propeller is and 2G. neutralized by 'the reverse rotation of the other, Between the engine housing and the gear housand consequentlysuch torsion stresses as exist ing iS arrangeda Support plete 22 having flanged are directly carried to the engine frame or hous- Central Opening 2'3- The Propellery drive Sleeve y structure are present. 'I'he invention involves the bearing 26 iS Positioned 0n the Sleeve 95 in the of gears is such that various reduction speeds may 40 collar 38'which may be secured to the sleeve in other propeller in the opposite direction; y the mannerof'av cantilever.

Itisacordingly an object of the invention to The other propeller drive sleeve it which is a d ual propeller drive in which a reduction gear 50 tation upon internal bearings de and 4'6, in turn rotation speeds may be provided tively of a support shank 48, forming a part of A further obJect of the invention 1s to provide the main support member 3 Y a dual propeller drive construction ofthe utmost 'I'he main support member of which' the sleeve simplicity, lightness and ruggedness` 55 portion is a part extends from the hangedl open- 2v I I, t ing 24 through thegear housing 4l forming the bearing support for the portion the entire assembly, the same taking extending on through ings inthe top and the shank propeller drive sleeve IB.- Between the shank and 'the sleeve portion main support member is cut away as indicated at 50 and 52 and as shown more particularly in `iiigure 2 in order that space may be provided for gearing to drive the propeller sleeves.

The drive means for thepropeller sleeves consist of a pair of internal gears 54 and 56, one

.on each of the drive sleeves lll and'l and lo- -4 cated within their and 42. An engine-driven shaft I8 connected tok the engine shaft I9 throughs. coupling 6I is jourrespective flared portions 32 naled eccentrically in the of the support plate flanged opening 24 and upon external bearings G0 and 62 located respectively in annular recesses in the end of the sleeve-like 64' and 66 formed portion 3G of the main support member 21, and

the inner end of the shank portion 48 respectively.' The drive ion i8 directlydriving the propeller sleeve I6. There is also provided a pinion 10 on the drive shaft which indirectly drives the internal gear I4 through a reversing idler pinion 12. This'latter pinion is Journaled through bearings 18 and 1I upon a'shprt shaft 14 extending between the sleeve-.like portion 36 and the rear end portion of the shank 48 of the main support member l1.

The main support integral member extending through the center of the form of the hollow sleeve portion a's' described at 36 and to the hollow shank portion 4I and the two portionsbeing connected together through a continuation `of the sleeve portion, which continuation is provided with openbottom to provide clearance for the drive gears. The 'sleeve portion may be provided with bulkheads 80 and 82 to assist in supporting the various bearings and lend rigidity thereto, and the whole assembly may be continuously supplied with' cool oil circulating in through'the tube 84 and out through the tube 86. This is made possible by the presence of the oil washer- 30 as well as the cap iece 8l arranged over the front end of the sleeve I6 and also the oil washer 90 arranged between lthe sleeves, by

reason of which the tight.

It will be understood that the sleeves are splined o r otherwise arranged to receive the propeller'hubs, and the same are clamped in place in any suitable manner. -It will also be understood thatthe'various gears employed may be changed by varying the pitch diameters so that any gear ratio to one or the other propeller may be obtained. In practice it is generally preferable to drive the inner propeller ata rotation speed approximately faster than the outer it'is desirable also'to drive both a speed much below'that of the engine crank shaft speed. It will thus be seen that there is provided a novel combination of parts which cooperate to form a gear drive-of extreme simplicity, strength, and satisfying all conditions.

Though a single embodiment ,of the invention has been illustrated and described, it is to be understood that the invention is 4not `limited thereto but may be embodied in various mechanical forms; As `many changes in construction and arrangement of parts may be made without vassembly is rendered oil 2,285,592 Y 'and merges into I departinogfrom the spirit of the invention, as will t be apparent 3B, however, the' i shaft 58 is provided with a pinthe internal gear 56 of member, as will appear from the description already set forth, is a continuous ruggedness, lightness and support member to' those skilled in the art,'re`f erence will be had totheappended claims" for a` tion of the limits of theinvention.

`What is claimed is:

l. In a dual propeller drive, a gear housing, a extending from the back of said housing and projecting out of vthe vfront thereof, a propeller drive sleeve journalled on said support member, a second propeller drive sleeve concentric with and` surrounding a portion of said first named sleeve and journalled in said housing, internal gearson each of said sleeves, one I' being vnested withinthevother,vv an idler pinion meshing with one ,of said internal gears, a drive shaft extending through the back of said housing having a pinion meshing withthe other internal gear and a pinion meshing with said idler pinion.

2. In a dual propeller drive gear, a centralsupport member havingfa shank portion merginginto' a hollow gear 'retaining portion of larger diameter than the shank portion, a; propeller drivesleeve journalled on said shank portionand having a flared end provided with an internally taining portion, a said hollow gear retaining portion in spaced relation, and secured thereto at the end opposite from the shank, a second propeller drive sleeve surrounding the first sleeve and terminatins casing member, and having a ared vend surrounding the ilared'end of said first mentioned sleeve and extendingtherebeyond and having an internally toothed gear therein, a drive shaft eccentric to said sleeves and journalled 'in said gear retaining portion and having a pinion meshing with one of said internal gears, a second pinion on said drive shaft, and an idler pinion journalled in said gear retaining meshing said secondpinion and the otherinternal gear.

3. In a dual propeller drive gear, a central support member having a shank portion merging into' a hollow gear retaining portion of larger diameter than the shank portion, a propeller casing member surrounding drive sleeve journalled on said shank portion and having a ilared'end provided with an internally toothed gearpartially surrounding said gear retaining portion, a casing member surrounding said -hollow gear etaining portion of the support in spaced relation, and secured thereto at the end opposite from the shank, a second propeller drive sleeve surrounding the first sleeve and terminat'- ing'short of the first sleeve and journalled in said casing member, and having a ared end surrounding the flared end of said first mentioned sleeve and extending therebeyond, and having an internally toothed gear therein, a drive shaft eccentric to said sleeves and journalleddn said gear retaining portion and having a pinion meshing with one of said internal gears, a second pinion on said drive shaft,` an idler pinion Journalled in said gear retaining portion and meshing 'with said second pnion and the other internal gear and means for. maintaining an oil tight seal to prevent oil leakage from said housing and support member.

4. In a dual propeller drive, a non-rotatablev toothed gear-partially surrounding said gear reof the support y short of the first sleeve and journalled in said portion and nalling said outer shaft.

5. In a dual supporting shaft,

mte

driving joursupporting shaft Vax'- ially beyond said enlarged housin '6.Inad

means carried by ling said ou ter sha JosEPH LEDWINKA.

non-roi'satabl'e 

